US STOCKS-Wal-Mart, materials shares drag Wall St lower
* Wal-Mart drops to 2-1/2 year low after weak results
* Disney, media companies hit by Wells Fargo downgrade
* Home Depot jumps after results; housing data strong
* Indexes down: Dow 0.19 pct, S&P 0.26 pct, Nasdaq 0.64 pct (Updates to close, changes comments, byline)
By Rodrigo Campos
Aug 18 (Reuters) - U.S. stocks fell on Tuesday, with the S&P 500 trading in its tightest daily range in nearly a month, weighed down by earnings-related selling in Wal-Mart and a drop in commodity stocks on concerns about China's economy.
Wal-Mart fell 3.4 percent to close at $69.48, its lowest in nearly 2-1/2 years, after its profit missed estimates and it cut its outlook.
Chinese stocks fell more than 6 percent overnight. Fears that Beijing may be intent on a deeper devaluation of the yuan pushed oil prices and industrial metals, including copper, to near six-year lows.
The materials sector was the largest decliner among the top ten industry sectors with a 0.7 percent decline. Freeport McMoRan fell 3.1 percent to $9.92. Continuación...